[ Upstream commit 561aa0e22b70a5e7246b73d62a824b3aef3fc375 ]
dma_map_XXX() functions return values DMA_MAPPING_ERROR as error values
which is often ~0. The error value should be tested with
dma_mapping_error().
This patch creates a new function in niu_ops to test if the mapping
failed. The test is fixed in niu_rbr_add_page(), added in
niu_start_xmit() and the successfully mapped pages are unmaped upon error.
Fixes: ec2deec1f3 ("niu: Fix to check for dma mapping errors.")
Signed-off-by: Thomas Fourier <fourier.thomas@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Thomas Fourier
56aebaaa3a